form-scraper

Scrape and Submit forms easily...

Usage no npm install needed!

<script type="module">
  import formScraper from 'https://cdn.skypack.dev/form-scraper';
</script>

README

Form Scraper - Scrape & Submit forms Easily...

The easiest way to fill forms from Node.JS

What's in Form Scraper for me?

The Problem

Sometimes you need to automate your form filling. However, the website that hosts the form, seeds some security tokens in the form. The security tokens are random and attached to your current session.

The Solution

You need to scrape the form first, including all the default values. Afterwards, you'll need to fill the details and submit the form.

form-scraper automates all the process.

Installation

$ npm install form-scraper

or add form-scraper to your package.json dependencies.

Usage

You can use form-scraper both in functional and object oriented way.

Functional usage

.fetchForm(formId, url, promisifiedRequest)

Fetches a form with formId from the specified url.

- arguments
  • formId - the id property of a form in a given html. Should be prefixed with "#".
  • url - The url that hosts the form.
  • promisifiedRequest - The request object (which returns promise) that performs the request.
- return value

The return value is a Promise which eventually should resolve to a JSON object with the following properties:

  • action - The url where the form should be submitted to.
  • data - A JSON hash object where the keys are the name properties of the form elemnts and the value is the default value.

.provideForm(promiseForForm)

Creates an object that implements the provideForm method.

- arguments
  • promiseForForm - a JSON object that represents the form.
- return value

The return value is an object that implements the provideForm method.

.submitForm(formValues, formProvider, promisifiedRequest)

Submits the form...

- arguments
  • formValues - a JSON hash object where the keys represent the property names and the values is the data to post.
  • formProvider - An object that implements the provideForm() method and returns a Promise for form.
  • promisifiedRequest - The request object (which returns promise) that performs the request.
- return value

The return value is a Promise which eventually should resolve to the response of the submission of the form.

example

var pRequest = require("promisified-request").create();
var fScraper = require("form-scraper");

var formStructure = fScraper.fetchForm("#login", "http://www.someurl.com", pRequest);
var loginDetails = { user: "my user", password: "my password" };

fScraper.submitForm(loginDetails, fScraper.provideForm(formStructure), pRequest).then( function (response) {
    console.log(response.body);
};

Object Oriented usage

As of today, the module consists of two classes:

  • form-scraper.ScrapingFormProvider - Scrapes the form.
  • form-scraper.FormSubmitter - Submits the form.

ScrapingFormProvider

.updateOptions(options)

Extends the current options. The default value is undefined, so it's important to inject the dependencies using this method.

Returns itself.

The options argument, should have the following values:

  • formId - The id of the Dom element that represents the form to scrape.
  • url - The url that hosts the form.
  • promisifiedRequest - The request object that will perform the scraping.
.provideForm()

Returns a promise that eventually will be resolved to the form structure.

FormSubmitter

.updateOptions(options)

Extends the current options. The default value is undefined, so it's important to inject the dependencies using this method.

Returns itself.

The options argument, should have the following values:

  • formProvider - An object that implements provideForm() and returns a promise for a form.
  • promisifiedRequest - The request object that will perform the submission.
.submitForm(formValues)

Submits the form with formValues.

formValues is a hash JSON object with values to post.

It returns a promise that eventually will be resolved to the response object that comes out of the request object.

example

var pRequest = require("promisified-request").create();
var fScraper = require("form-scraper");

var loginDetails = { user: "my user", password: "my password" };

var formProvider = new fScraper.ScrapingFormProvider();
var formSubmitter = new fScraper.FormSubmitter();

formProvider.updateOptions({
    formId: "#login",
    url: "http://www.somedomain.com",
    promisifiedRequest: pRequest
});

formSubmitter
    .updateOptions({
        formProvider: formProvider,
        promisifiedRequest: pRequest
    })
    .submitForm(loginDetails)
        .then(function(response) {
            console.log(response.body);
        });